Mo-Doped FeP Nanospheres for Artificial Nitrogen Fixation

Electrochemical conversion of N₂ to NH₃ under ambient conditions is a promising and environmentally friendly route compared with the CO₂-emitting and energy-intensive Haber–Bosch process. Nevertheless, due to ultrahigh stability of N₂, it is urgent to explore efficient catalysts to weaken and activate the N≡N bond. Here, we report the Mo-doped iron phosphide (Mo-FeP) nanosphere as a valid transition-metal-based catalyst for electrochemical N₂-to-NH₃ fixation under ambient conditions. This catalyst exhibits excellent catalytic performance with a NH₄⁺ yield rate (13.1 μg h^–1 mg^–1) and Faradaic efficiency (7.49%) at −0.3 and −0.2 V vs reversible hydrogen electrode (RHE), respectively. However, the FeP catalyst without doped Mo species displays weak catalytic performance. We found that the better catalytic performance of Mo-FeP might be due to the doping of Mo species, which is favorable for the polarization of adsorbed N₂ molecules, making the N≡N bond more viable to dissociate.